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Inspection Procedure

NOTE: The vehicle is equipped with an SRS (Supplemental Restraint System) which includes components such as airbags. Before servicing (including removal or installation of parts), be sure to read the PRECAUTION for the supplemental restraint system (see PRECAUTION ).
  1. INSPECT STEERING PAD SWITCH ASSEMBLY 
    Fig 1: Inspecting Steering Pad Switch Assembly
    G05819653Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the switch connector.
    2. Measure the resistance of the switch.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester connection Condition Specified condition
      A-9 (AU2) - A-8 (EAU) No switch Is pushed 95 to 105 kΩ
      A-9 (AU2) - A-8 (EAU) MODE switch pushed Below 2.5 Ω
      A-9 (AU2) - A-8 (EAU) ON HOOK switch pushed 313.5 to 346.5 Ω
      A-9 (AU2) - A-8 (EAU) OFF HOOK switch pushed 959.5 to 1060.5 Ω
      A-9 (AU2) - A-8 (EAU) VOICE switch pushed 3049.5 to 3370.5 Ω
      A-10 (AU1) - A-8 (EAU) No switch is pushed 95 to 105 kΩ
      A-10 (AU1) - A-8 (EAU) SEEK+ switch pushed Below 2.5 Ω
      A-10 (AU1) - A-8 (EAU) SEEK- switch pushed 313.5 to 346.5 Ω
      A-10 (AU1) - A-8 (EAU) VOL+ switch pushed 959.5 to 1060.5 Ω
      A-10 (AU1) - A-8 (EAU) VOL- switch pushed 3049.5 to 3370.5 Ω

    NG: REPLACE STEERING PAD SWITCH ASSEMBLY 

    OK: Go to Next Step 

  2. INSPECT SPIRAL CABLE 
    1. Disconnect the cable connectors.
    2. Measure the resistance of the cable.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester connection Spiral Cable Position Specified condition
      K20-4 (EAU) - A-8 (EAU) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right
      K20-5 (AU2) - A-9 (AU2) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right
      K20-6 (AU1) - A-10 (AU1) Center Below 1 Ω
      2.5 rotations to the left
      2.5 rotations to the right
      NOTE: The spiral cable is an important part of the SRS airbag system. Incorrect removal or installation of the spiral cable may prevent the airbag from deploying. Be sure to read the PRECAUTION for the supplemental restraint system (see PRECAUTION ).
      Fig 2: Inspecting Spiral Cable
      G05819654Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE SPIRAL CABLE SUB-ASSEMBLY 

    OK: Go to Next Step 

  3. CHECK WIRE HARNESS (SPIRAL CABLE - RADIO RECEIVER) 
    1. Disconnect the K56 receiver connector.
    2. Disconnect the K20 cable connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      K56-8 (SW2) - K20-5 (AU2) Below 1 Ω
      K56-6 (SWG) - K20-4 (EAU) Below 1 Ω
      K56-7 (SW1) - K20-6 (AU1) Below 1 Ω
      K56-8 (SW2) - Body ground 10 kΩ or higher
      K56-6 (SWG) - Body ground 10 kΩ or higher
      K56-7 (SW1) - Body ground 10 kΩ or higher
      4. Fig 3: Identifying K56 Receiver And K20 Cable Connector Terminals
      G05819655Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: PROCEED TO NEXT INSPECTION PROCEDURE SHOWN IN  PROBLEM SYMPTOMS TABLE  

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